Linear motion, re-circulating ball, sliding support assemblies for light-duty applications are known in the art. Such support assemblies allow a variety of potential setups to be achieved in order to move objects along a linear rail. Such rails can be made from extruded lengths of aluminium of, for example, 1 m or 2 m in length. The lengths of rail can be cut to length, drilled or machined as required by the user.
Such sliding supports include a slide cassette and a plurality of bearing balls. The slide cassette is typically made from one or two polymer or resin components, and/or a pressed stainless steel, or nitrided steel member. The slide cassette can be arranged within a length of rail chosen by the user.
For example, U.S. Pat. No. 4,701,057 discloses a sliding support assembly comprising a linear rail having a web and a pair of flanges. The inner surface of each flange includes a first linear guide groove. The assembly includes a slider unit including a pair of endless circulating paths in which a plurality of bearing balls can move. The slider unit includes a main body comprised of upper and lower body sections moulded from plastic material, in which the endless paths are defined, and a frame attached to the main body. The frame comprises a channel-section member having a pair of linear second guide grooves formed in the outer surface of the member's flanges. The linear second guide grooves extend in opposed relation to the corresponding first guide grooves, and partly define the endless paths. Similar slide assemblies are disclosed in U.S. Pat. No. 5,518,317 and EP 1 363 036.
However, there are no known re-circulating ball slide assemblies having a slide cassette arranged within a rail which are adapted for heavy-duty applications, such as heavy doors for hospitals or offices. In heavy-duty applications low friction is especially important to reduce the force required to operate the slide.
Accordingly, there is a need for an improved re-circulating ball sliding support assembly adapted for heavy-duty applications.